package com.yzh.design.demo;

/**
 * 使用类的内部类（线程安全）
 */
public class Singleton_04 {
    private static class SingletonHolder {
        private static Singleton_04 instance = new Singleton_04();
    }

    private Singleton_04() {
    }

    public static Singleton_04 getInstance() {
        return SingletonHolder.instance;
    }
}
